A real-world test performed by the Dutch province of Zeeland. Twelve small wind generators were placed in a row on an open plain. Their energy yield was measured over a period of one year, the average wind velocity during these 12 months was 3.8 meters per second. Three windmills broke.

Interesting tests, judging by that, it looks to me like the skystream takes the win, although it comes second in raw output, it is almost half the price of the top generator and has smaller blades, and the difference in power generation isn’t really very big. With the bigger wind speeds available out to sea, I would expect one of those could power a homestead quite comfortably.

What about verticle axis windmills? I’ve seen a model that costs $400 and can conservatively kick out 40 kwh in a months time. Thats not a whole lot, but the big windmills might be too big for early seastead applications.

I figure the 40 kwh figure may actually be low because it can get quite windy out on the open sea. And 40 kwh is about the monthly energy usage for lighting a 3500 sq. foot house in a month. Use high efficiency LED or CFL lighting and thats even better.

The cost of steel to make a big tower and slap a big turbine on top may be cost prohibitive versus a few vertical windmills and a smattering of batteries, especially if you are talking about single family seasteads. Larger units, where modularity is not the desire, will probably do better with larger turbines.

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There is no fate but what we make for ourselves. Each to his fate.

Even a single family seastead is going to need 6-8 of the larger 4-5m diameter windmills to be self-sufficient. The study says you would need 6 of the Montana or Skystream windmills to power a typical American house…and most American households aren’t running desalinization, hydroponic, or fish hatchery facilities let alone station keeping-engines.

The study recommends that you always look for a single, larger windmill to meet your needs, rather than relying on multiple, smaller windmills.

I wonder, would it be more practical to run a smaller seastead on gas generator? Its far more expensive than grid electricity, but wind solar and wave have huge upfront costs. There really doesn’t seem to be a good solution to powering seasteads. Its definitely the biggest technical problem. Early seasteaders are going to have to find whatever solution is “less bad”.

Seasteads themselves have a huge upfront cost… far more than that of a series of horizontal, or one or two big vertical, windmills. With more constant, and stronger, winds on the oceans, fewer windmills would be needed to power a structure. Several vertical turbines on the windward side of a structure should be sufficient to power a modest seastead. Larger structures would do well with, not oddly, larger windmills.

Finding viable power supplies will not be the biggest issue that plagues the creation of seasteads, however. Design and funding will be greater hurdles to overcome, in my estimation.

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There is no fate but what we make for ourselves. Each to his fate.

“The study recommends that you always look for a single, larger windmill to meet your needs, rather than relying on multiple, smaller windmills.”

The study is not taking other factors into account, only price and total generation capacity. Most studies with an urban focus in mind will not be worried about redundancy, for example. Mounting of the windmill is only mentioned in passing, towards the end as well.

Clearly, issues of scaling are a major factor in design considerations. The study seems dismissive of design consideration other than size- while size would pretty clearly be a major factor, I can’t believe that design is that unimportant. It seems the study starts out to debunk the idea of small urban windmills. While it may be important from a policy standpoint to do so, that doesn’t mean it’s great science.

I think the vertical windmills are definitely looking in to. They’d be much simpler to work with. I think I remember reading that several kinds of vertical-axis windmills can operate at lower windspeeds than horizontal systems, as well.

Vertical axis wind turbines seem to be very rare out in the real world. At least here in Europe. There are probably good reasons for this. For one thing, the airfoils on a VAWT are subject to changing angles of attack from the wind during the course of rotation. Apparently this can produce pulsating forces that probably take their toll on the structure over time and perhaps makes them noisier.